Neil Brown <neilb@xxxxxxx> wrote:
>
> ...
> Reduce stack usage with stacked block devices
>
> ...
> diff ./include/linux/sched.h~current~ ./include/linux/sched.h
> --- ./include/linux/sched.h~current~ 2005-11-07 10:01:36.000000000 +1100
> +++ ./include/linux/sched.h 2005-11-07 10:02:23.000000000 +1100
> @@ -829,6 +829,9 @@ struct task_struct {
> /* journalling filesystem info */
> void *journal_info;
>
> +/* stacked block device info */
> + struct bio *bio_list, **bio_tail;
> +
> /* VM state */
> struct reclaim_state *reclaim_state;
>
More state in the task_strut is a bit sad, but not nearly as sad as deep
recursion in our deepest codepath..
Possibly one could do:
struct make_request_state {
struct bio *bio_list;
struct bio **bio_tail;
};
and stick a `struct make_request_state *' into the task_struct and actually
allocate the thing on the stack. That's not much nicer though.
--
dm-devel@xxxxxxxxxx
https://www.redhat.com/mailman/listinfo/dm-devel
